23 android广播包的解析

// Helper Classes: BleUtil and BleAdvertisedData
final class BleUtil {
    public static BleAdvertisedData parseAdertisedData(byte[] advertisedData) {
        List<UUID> uuids = new ArrayList<UUID>();
        String name = null;
        byte[] data = null;
        if (advertisedData == null) {
            return new BleAdvertisedData(uuids, name);
        }

        ByteBuffer buffer = ByteBuffer.wrap(advertisedData)
                .order(ByteOrder.LITTLE_ENDIAN);

        while (buffer.remaining() > 2) {
            byte length = buffer.get();
            if (length == 0)
                break;

            byte type = buffer.get();
            switch (type) {
            case 0x02: // Partial list of 16-bit UUIDs
            case 0x03: // Complete list of 16-bit UUIDs
                while (length >= 2) {
                    uuids.add(UUID.fromString(
                            String.format("%08x-0000-1000-8000-00805f9b34fb",
                                    buffer.getShort())));
                    length -= 2;
                }
                break;
            case 0x05: // Complete list of 32-bit UUIDs
                while (length >= 4) {
                    uuids.add(UUID.fromString(
                            String.format("%016x-0000-1000-8000-00805f9b34fb",
                                    buffer.getInt())));
                    length -= 4;
                }
                break;
            case 0x06: // Partial list of 128-bit UUIDs
            case 0x07: // Complete list of 128-bit UUIDs
                while (length >= 16) {
                    long lsb = buffer.getLong();
                    long msb = buffer.getLong();
                    uuids.add(new UUID(msb, lsb));
                    length -= 16;
                }
                break;
            case 0x09: // Complete local name
                byte[] nameBytes = new byte[length - 1];
                buffer.get(nameBytes);
                try {
                    name = new String(nameBytes, "utf-8");
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
                break;
            case 0x16: // Service data
                if (uuid128To16bit(BleLink.SERVICE_UUID) != buffer.getShort()) {
                    IwdsLog.d(MasterBleLink.TAG, "don't care the service data");

                    break;
                }
                data = new byte[length - 3];
                buffer.get(data);
                break;
            default:
                buffer.position(buffer.position() + length - 1);
                break;
            }
        }
        return new BleAdvertisedData(uuids, name, data);
    }

    private static short uuid128To16bit(String serviceUuid) {
        String uuid16bit = serviceUuid.substring(4, 8);
        return Integer.decode("0x" + uuid16bit).shortValue();
    }
}

// 自定义广播包的格式信息
class BleAdvertisedData {
    private List<UUID> mUuids;
    private String mName;
    private byte[] mData;

    public BleAdvertisedData(List<UUID> uuids, String name) {
        this(uuids, name, null);
    }

    public BleAdvertisedData(List<UUID> uuids, String name, byte[] data) {
        mUuids = uuids;
        mName = name;
        mData = data;
    }

    public List<UUID> getUuids() {
        return mUuids;
    }

    public String getName() {
        return mName;
    }

    public byte[] getServiceData() {
        return mData;
    }
}